State stream game engine

ABSTRACT

The present disclosure provides a state stream game engine for a video game application. The state stream game engines can decouple the simulation of a video game application from the rendering of the video game application. The simulation of the video game is handled by a simulation engine. The rendering of the video game is handled by a presentation engine. The data generated by the simulation engine can be communicated to the presentation engine 124 using a state stream.

INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS

Any and all applications for which a foreign or domestic priority claimis identified in the Application Data Sheet as filed with the presentapplication are incorporated by reference under 37 CFR 1.57 and made apart of this specification.

BACKGROUND

Video games have increased in popularity and complexity in recent years.Today's video games have many more features and can be much more complexthan video games of the past. The video games can have many differentprocesses being performed on the CPU and the GPU. Generally, the CPU canexecute the game logic, also referred to as the simulation, and the GPUcan render frames, also referred to as the presentation, that are outputand displayed to the user. The simulation and rendering have manydependencies, which can be difficult to manage. It can be difficult tosynchronize the simulation and rendering processes in order to createsmooth and reliable performance within a video game.

SUMMARY OF EMBODIMENTS

The systems, methods, and devices of this disclosure each have severalinnovative aspects, no single one of which is solely responsible for theall of the desirable attributes disclosed herein.

Some aspects of the present disclosure feature a computer-implementedmethod for executing a game application on a user computing system: byone or more hardware processor configured with computer executableinstructions, executing a game application; executing a plurality ofsimulation engines within the game application, wherein each simulationengine is configured to execute game logic that is configured to controlsimulation of a virtual environment within the game application, whereineach simulation engine is configured to control simulation of adifferent virtual environment, wherein each virtual environmentcomprises a plurality of virtual objects registered to the correspondingsimulation engine; for each simulation engine, generating simulationstate data for each virtual object registered to the simulation engineduring a simulation cycle; generating graphical state data based atleast in part on the simulation state data generated for the simulationcycle; writing the graphical state data for a least a subset of thevirtual objects to a state data package during the simulation cycle;after the graphical state data for each virtual object has been writtento the state data package, writing the state data package to a statestream during the simulation cycle, wherein the state stream is aportion of volatile memory allocated to receive the state data package;executing a presentation engine within the game application, wherein thepresentation engine is configured to generate and render frames foroutput on a display; selecting, by the presentation engine, at least afirst state data package of a plurality of state data packages during arendering cycle; reading, by the presentation engine, at least the firststate data package from the state stream during the rendering cycle;updating, by the presentation engine, a graphical state of first virtualenvironment corresponding to the virtual environment associated with thefirst state data package, generating, by the presentation engine, aframe based at least in part on the updated graphical state of the firstvirtual environment and a second state data package, wherein the secondstate data package was generated by the same simulation engine thatgenerated the first state data package; and rendering, by thepresentation engine, the frame based at least in part on the graphicalstate data included in the first state data package and the second statedata package during the rendering cycle, wherein the presentation enginestate data package generates, wherein the presentation engine executesthe rendering cycles without further input from the simulation enginesafter receiving the state data packages.

Various embodiments of the system may include one, all, or anycombination of the following features. The simulation cycle and therendering cycle are the different lengths of time. Interpolating thegraphical state data included in the first state data package and thesecond state data package; generating a plurality of frames based on theinterpolation; and rendering the plurality of frames. The simulationcycles for each simulation engine are different lengths of time relativeto each other. The each of the plurality of simulation engines executeindependent of each other and the presentation engine, wherein thepresentation engine generates and renders frames independent of theexecution of simulation engine that generated the state data package.Executing one or more simulation engines on different user computingsystems and writing state data packages to the state stream on the usercomputing system over a network. By each simulation engine, writingstate data package to a location in non-volatile storage simultaneouslywith writing the state data package to the state stream. Each simulationengine writes to a different state stream, and each state stream isallocated a different portion of volatile memory to receive the statedata package. Determining, by the presentation engine, an state datapackage is ready for disposal; and deleting the state data packages fromthe state stream that are ready for disposal. The graphical state dataof a state data package comprises state data necessary to recreate agraphical scene within the respective virtual environment of thecorresponding simulation engine at a point in time. The state datapackage is generated in less time that the length of the simulationcycle, wherein there is a period of time between writing the state datapackage to the state stream and the initiation of the subsequentsimulation cycle.

Some aspects of the present disclosure feature a computing systemcomprising: one or more hardware processors configured withcomputer-executable instructions that configure the computing system to:execute a game application; execute a plurality of simulation engineswithin the game application, wherein each simulation engine isconfigured to execute game logic that is configured to controlsimulation of a virtual environment within the game application, whereineach simulation engine is configured to control simulation of adifferent virtual environment, wherein each virtual environmentcomprises a plurality of virtual objects registered to the correspondingsimulation engine; for each simulation engine, generate simulation statedata for each virtual object registered to the simulation engine duringa simulation cycle; generate graphical state data based at least in parton the simulation state data generated for the simulation cycle; writethe graphical state data for a least a subset of the virtual objects toa state data package during the simulation cycle; after the graphicalstate data for each virtual object has been written to the state datapackage, write the state data package to a state stream during thesimulation cycle, wherein the state stream is a portion of volatilememory allocated to receive the state data package; execute apresentation engine within the game application, wherein thepresentation engine is configured to generate and render frames foroutput on a display; select, by the presentation engine, at least afirst state data package of a plurality of state data packages during arendering cycle; read, by the presentation engine, at least the firststate data package from the state stream during the rendering cycle;update, by the presentation engine, a graphical state of first virtualenvironment corresponding to the virtual environment associated with thefirst state data package, generate, by the presentation engine, a framebased at least in part on the updated graphical state of the firstvirtual environment and a second state data package, wherein the secondstate data package was generated by the same simulation engine thatgenerated the first state data package; and render, by the presentationengine, the frame based at least in part on the graphical state dataincluded in the first state data package and the second state datapackage during the rendering cycle, wherein the presentation enginestate data package generates, wherein the presentation engine executesthe rendering cycles without further input from the simulation enginesafter receiving the state data packages.

Various embodiments of the system may include one, all, or anycombination of the following features. The simulation cycle and therendering cycle may be different lengths of time. The one or moreprocessors may be configured with computer-executable instructions thatfurther configure the presentation engine to interpolate the graphicalstate data included in the first state data package and the second statedata package, generate a plurality of frames based on the interpolation,and render the plurality of frames. the simulation cycles for eachsimulation engine have different lengths of time relative to each other.The one or more processors are configured with computer-executableinstructions that further configure each of the plurality of simulationengines to execute independent of each other and the presentationengine, the presentation engine to generate and render framesindependent of the execution of simulation engine that generated thestate data package. The one or more processors are configured withcomputer-executable instructions that further configure each simulationengine to write the state data package to a location in non-volatilestorage simultaneously with writing the state data package to the statestream. The one or more processors are configured withcomputer-executable instructions that further configure each simulationengine writes to a different state stream, and each state stream isallocated a different portion of volatile memory to receive the statedata package. The graphical state data of a state data package comprisesstate data necessary to recreate a graphical scene within the respectivevirtual environment of the corresponding simulation engine at a point intime. The state data package is generated in less time that the lengthof the simulation cycle, wherein there is a period of time betweenwriting the state data package to the state stream and the initiation ofthe subsequent simulation cycle.

Although certain embodiments and examples are disclosed herein,inventive subject matter extends beyond the examples in the specificallydisclosed embodiments to other alternative embodiments and/or uses, andto modifications and equivalents thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

Throughout the drawings, reference numbers are re-used to indicatecorrespondence between referenced elements. The drawings are provided toillustrate embodiments of the subject matter described herein and not tolimit the scope thereof.

FIG. 1 illustrates an embodiment of a computing environment that canimplement one or more embodiments of a state stream video game engine.

FIGS. 2A-2F provide embodiments of block diagrams illustratingfunctionality of a state stream video game engine.

FIG. 3 illustrates an embodiment of a block diagram of a state streamgame engine configured to implement replay functionality.

FIG. 4 illustrates an embodiment of a block diagram of a state streamgame engine configured to implement multiple simulation engines 122.

FIG. 5 illustrates an embodiment of a computing environment forimplementing an embodiment of the state stream game engine in amultiplayer game application.

FIGS. 6A-6B illustrate an embodiment of a flowchart of a process forexecuting a game application using a state stream game engine.

FIGS. 7A-7B illustrate an embodiment of a flowchart of a process forexecuting a game application using multiple simulation engines 122 in astate stream game engine.

FIG. 8 illustrates an embodiment of a computing device.

DETAILED DESCRIPTION OF EMBODIMENTS Overview

One of the difficulties in managing video games is that the processescan be difficult synchronize the simulation and presentation, especiallyas the games get larger in size and more complex. There can be manydependencies between the simulation of a video game and the rendering ofthe frames for presentation of the video game. If any of the aspects ofthe video game simulation lag behind other components, it can createproblems with the rendering of frames and presentation to the user. Thiscan result in inconsistencies in the rendering and presentation ofgameplay, such as an inconsistent frame rate, which can reduce thequality of the user experience.

The present application provides a solution to this problem by using astate stream game engine. The state stream game engines can decouple thesimulation of a video game application from the rendering of the videogame application. The simulation of the video game is handled by asimulation engine 122. The rendering of the video game is handled by apresentation engine 124. The data generated by the simulation engine 122can be communicated to the presentation engine 124 using a state stream.

The simulation engine 122 can execute the game logic and controlexecution of the game application. The simulation engine 122 can run inits own thread independent of the execution of the presentation engine124. The simulation engine 122 can write state modifications in the formof a state stream data package (referred to herein as an “SSDP”) to thestate stream. Communication between the between the simulation engine122 and the state stream can generally be is one directionalcommunication, where the simulation engine 122 writes the SSDP to thestate stream. The simulation engine 122 publishes a SSDP after it isgenerated during a simulation cycle and writes the SSDP to the statestream. The presentation engine 124 cannot access the SSDP until it ispublished to the state stream. After the SSDP is finished and published,the simulation engine 122 can begin writing a new SSDP. For example,state (n) is propagated through to state (n+1), and state (n+1) becomescurrent state. The simulation engine 122 can publish an SSDP at adefined interval, such as 30 hz. In some embodiments, the SSDP can begenerated as soon as a previous simulation cycle is completed. Thesimulation engine 122 generates graphical state data based on simulationstate data. The graphical state data is based on the simulation statedata and can include state data that is necessary for the presentationengine 124 to generate a scene within the virtual environment at thepoint in time that the simulation data is generated. The graphical statedata can be a subset of the simulation state data associated with thestate of the game application when the SSDP is generated. Thepresentation can use the graphical state data to render a frame withinthe virtual environment for presentation.

The presentation engine 124 can read SSDPs from state stream. Generally,the presentation engine 124 does not write to the state stream. Thepresentation engine 124 can run rendering in its own thread, independentof the simulation engine 122. The SSDPs can store all the graphicalstate data needed by the presentation engine 124 for rendering a frame.The graphical state data may include static state data, which is thesame for the entire lifetime of an object, and dynamic state data, whichcan change over the lifetime of an object. The presentation engine 124can interpolate the graphical state data from multiple SSDPs in order togenerate and render frames at a higher frequency than the SSDPs aregenerated by the simulation engine 122. The presentation engine 124 canbe responsible for disposing of SSDPs in the state stream after theSSDPs are consumed for rendering. The presentation engine 124 may notuse a generated SSDP. For example, the simulation engine 122 maygenerate SSDPs that are never used by the presentation engine 124. Insome embodiments, the presentation engine 124 and can use multiple SSDPsto compose a frame and/or render a sequence of frames. The SSDPs can beconfigured so that they include no dependencies back to the simulationengine 122. This allows the presentation engine 124 to use the SSDPsindependent of the execution of the simulation engine 122. In someembodiments, the presentation engine 124 can use states from differentsimulation engines 122.

While the description above focused on utilizing state stream gameengine in video game applications, it may be understood that thetechniques described herein may be applied to different use cases. Forexample, state stream game engine may be utilized for other types ofsoftware applications. For example, the simulation may be based onapplication logic that is used by a game announcer for an e-sports videogame tournament. The video game announcer may have an announcerapplication that has its own simulation engine 122 and utilizesgraphical state data received from a plurality of different computingsystems associated with players executing a game application. Theannouncer application can generate and render frames based on SSDPsreceived from player's computing systems.

Overview of Video Game Environment

FIG. 1 illustrates an embodiment of a computing environment 100 forimplementing a state stream game engine 120. The environment 100includes a network 108, a user computing system 102, and an interactivecomputing system 130, which includes at least application host systems122, and a data store 124. To simplify discussion and not to limit thepresent disclosure, FIG. 1 illustrates only one user computing system102, and one interactive computing system 130, though multiple systemsmay be used.

The user computing system 102 may communicate via a network 108 with theinteractive computing system 130. Although only one network 108 isillustrated, multiple distinct and/or distributed networks 108 mayexist. The network 108 can include any type of communication network.For example, the network 108 can include one or more of a wide areanetwork (WAN), a local area network (LAN), a cellular network, an ad hocnetwork, a satellite network, a wired network, a wireless network, andso forth. In some embodiments, the network 108 can include the Internet.

A. User Computing Systems

The user computing system 102 may include hardware and softwarecomponents for establishing communications over a communication network108. For example, the user systems 102 may be equipped with networkingequipment and network software applications (for example, a web browser)that facilitate communications via one or more networks (for example,the Internet or an intranet). The user computing system 102 may havevaried local computing resources 104, such as central processing units(CPU) and architectures, memory, mass storage, graphics processing units(GPU), communication network availability and bandwidth, and so forth.Further, the user computing system 102 may include any type of computingsystem. For example, the user computing system 102 may include any typeof computing device(s), such as desktops, laptops, video game platforms,television set-top boxes, televisions (for example, Internet TVs),network-enabled kiosks, car-console devices computerized appliances,wearable devices (for example, smart watches and glasses with computingfunctionality), and wireless mobile devices (for example, smart phones,PDAs, tablets, or the like), to name a few. In some embodiments, theuser computing system 102 may include one or more of the embodimentsdescribed below with respect to FIG. 8.

1. Game Application

The user computing system 102 can execute a game application 110 basedon software code stored at least in part in the application data store106. The game application 110 may also be referred to as a video game, agame, game code and/or a game program. A game application 110 should beunderstood to include software code that a computing device 102 can useto provide a game for a user to play. A game application 110 maycomprise software code that informs a computing device 102 of processorinstructions to execute, but may also include data used in the playingof the game, such as data relating to game simulation, rendering,animation, and other game data.

In the illustrated embodiment, the user computing system 102 is capableof executing machine readable instructions that are configured toexecute the game application 110 stored on a data store on the usercomputing system (e.g., application data store 106). The gameapplication 110, when executed, includes a state stream game engine 120,game data 114, and game state information 116. The game application,when executed, is configured to generate a virtual environment for auser to interface with the game application 110.

In some embodiments, the user computing system 102 may be configured toexecute a game application 110 stored and/or executed in a distributedenvironment using a client/server architecture. For example, the usercomputing system 102 may execute a portion of a game application 110 andthe interactive computing system 130, or an application host system 132of the interactive computing system 130, may execute another portion ofthe game application 110. For instance, the game application may be amassively multiplayer online role-playing game (MMORPG) that includes aclient portion executed by the user computing system 102 and a serverportion executed by one or more application host systems 132. The gameapplication 110 can execute on the user computing system 102 or adistributed application that includes a portion that executes on theuser computing system 102 and a portion that executes on at least one ofthe application host systems 122. In some embodiments, the gameapplication 110 may execute entirely on the interactive computing system130, and the interactive computing system130 may stream the gameplay ofthe game application 110 to the user computing system 102 over thenetwork 108.

i. State Stream Game Engine

During operation, the state stream game engine 120 executes the gamelogic, controls execution of the simulation of gameplay, and renderingwithin the game application 110. The state stream game engine 120 caninclude a simulation engine 122 and a presentation engine 124 (asillustrated in FIGS. 2A and 2B). The simulation engine 122 can executethe game logic and control execution of gameplay simulation. Thepresentation engine 124 can control execution of rendering of gameplayframes and the output of the presentation of the frames.

The simulation engine 122 can read in game rules and generates gamestate based on input received from one or more users. The simulationengine 122 can control execution of individual objects, such as virtualcomponents, virtual effects and/or virtual characters, within the gameapplication. The simulation engine 122 can manage and determinecharacter movement, character states, collision detection, derivedesired motions for characters based on collisions. The simulationengine 122 receives user inputs and determines character events, such asactions, collisions, runs, throws, attacks and other events appropriatefor the game. The character events can be controlled by charactermovement rules that determine the appropriate motions the charactersshould make in response to events. The simulation engine 122 can includea physics engine that can determine new poses for the characters. Thephysics engine can have as its inputs, the skeleton models of variouscharacters, environmental settings, character states such as currentposes (for example, positions of body parts expressed as positions,joint angles or other specifications), and velocities (linear and/orangular) of body parts and motions provided by a character movementmodule, which can be in the form of a set of force/torque vectors forsome or all body parts. From this information, the physics enginegenerates new poses for the characters using rules of physics and thosenew poses can be used to update character states. The simulation engine122 provides for user input to control aspects of the game applicationaccording to defined game rules. Examples of game rules include rulesfor scoring, possible inputs, actions/events, movement in response toinputs, and the like. Other components can control what inputs areaccepted and how the game progresses, and other aspects of gameplay.

The simulation engine 122 can output graphical state data that is usedby presentation engine 124 to generate and render frames within the gameapplication. Each virtual object can be configured as a state streamprocess that is handled by the simulation engine 122. Each state streamprocess can generate graphical state data for the presentation engine124. For example, the state stream processes can include various virtualobjects, such as emitters, lights, models, occluders, terrain, visualenvironments, and other virtual objects with the game application thataffect the state of the game. The execution of the simulation engine 122is described in further detail herein.

The presentation engine 124 can use the graphical state data to generateand render frames for output to a display within the game application.The presentation engine 124 can combine the virtual objects, such asvirtual characters, animate objects, inanimate objects, backgroundobjects, lighting, reflection, and the like, in order to generate a fullscene and a new frame for display. The presentation engine 124 takesinto account the surfaces, colors textures, and other parameters duringthe rendering process. The presentation engine 124 can combine thevirtual objects (e.g., lighting within the virtual environment andvirtual character images with inanimate and background objects) togenerate and render a frame. The execution of the presentation engine124 is described in further detail herein.

ii. Game Data

The game data 114 can include game rules, prerecorded motion captureposes/paths, environmental settings, environmental objects, constraints,skeleton models, route information, and/or other game applicationinformation. At least a portion of the game data 114 can be stored inthe application data store 106. In some embodiments, a portion of thegame data 114 may be received and/or stored remotely, such as in thedata store 134, in such embodiments, game data may be received duringruntime of the game application.

iii. Game State Data

During runtime, the game application 110 can store game state data 116,which can include a game state, character states, environment states,scene object storage, route information and/or other informationassociated with a runtime state of the game application 110. Forexample, the game state data 116 can identify the state of the gameapplication 110 at a specific point in time, such as a characterposition, character orientation, character action, game levelattributes, and other information contributing to a state of the gameapplication. The game state data 116 can include simulation state dataand graphical state data. The simulation state data includes the gamestate data that is used by the simulation engine 122 to execute thesimulation of the game application. The graphical state data includesgame state data that is generated based on the simulation state data andis used by the presentation engine 124 to generate and render frames foroutput, such as to a display of the user computing system 102. Thegraphical state data can be generated by the state stream processes andincluded in an SSDP.

B. Interactive Computing System

The interactive computing system 130 can include one or more applicationhost systems 132 and account data store(s) 134. The interactivecomputing system 130 may include one or more computing systemsconfigured to execute a portion of the game application 110 and/or hostapplication 106. In some embodiments, the one or more application hostsystems 122 can include one or more computing devices, such as serversand databases that may host and/or execute a portion of one or moreinstances of the game application 110 and/or a host application (notshown). In certain embodiments, instead of or in addition to executing aportion of the game application 110 and/or host application, theapplication host systems 122 may execute another application, which maycomplement and/or interact with the application 104 during execution ofan instance of the application 104.

1. Application Host System(s)

The interactive computing system 130 may enable multiple users orcomputing systems to access a portion of the game application 110 and/orhost application 106 executed or hosted by the interactive computingsystem 130. In some embodiments, the portion of the game application 110executed by application host systems 132 of the interactive computingsystem 130 may create a persistent virtual world. This persistentvirtual world may enable one or more users to interact with the virtualworld and with each other in a synchronous and/or asynchronous manner.In some cases, multiple instances of the persistent virtual world may becreated or hosted by the interactive computing system 130. A set ofusers may be assigned to or may access one instance of the persistentvirtual world while another set of users may be assigned to or mayaccess another instance of the persistent virtual world.

In some embodiments, the host application system 132 may execute ahosting system for executing various aspects of a game environment. Forexample, in one embodiment, the game application 110 may be acompetitive game, such as a first person shooter or sports game, and thehost application system 132 can provide a dedicated hosting service forhosting multiplayer game instances or facilitate the creation of gameinstances hosted by user computing devices. In some embodiments, thehost application system 132 can provide a lobby or other virtualenvironment for users to virtually interact with one another. Suchenvironments may include environments for conducting transactionsbetween players, such as an auction house or type of environment forfacilitating transactions.

2. Account Data Store

The interactive computing system 130 can include one or more accountdata stores 134 that are configured to store user account informationassociated with game applications hosted by the interactive computingsystem 130 and/or the application host systems 132.

Virtual Environment

As used herein, a virtual environment may comprise a simulatedenvironment (e.g., a virtual space) instanced on a user computing system102. The virtual environment may be instanced on a server (e.g., anapplication host system 132 of the interactive computing system 130)that is accessible by a client (e.g., user computing system 102) locatedremotely from the server, to format a view of the virtual environmentfor display to a user of the client. The simulated environment may havea topography, express real-time interaction by the user, and/or includeone or more objects positioned within the topography that are capable oflocomotion within the topography. In some implementations, thetopography may be a 2-dimensional topography. In other instances, thetopography may be a 3-dimensional topography. In some implementations,the topography may be a single node. The topography may includedimensions of the virtual environment, and/or surface features of asurface or objects that are “native” to the virtual environment. In someimplementations, the topography may describe a surface (e.g., a groundsurface) that runs through at least a substantial portion of the virtualenvironment. In some implementations, the topography may describe avolume with one or more bodies positioned therein (e.g., a simulation ofgravity-deprived space with one or more celestial bodies positionedtherein). A virtual environment may include a virtual world, but this isnot necessarily the case. For example, a virtual environment may includea game space that does not include one or more of the aspects generallyassociated with a virtual world (e.g., gravity, a landscape, etc.). Byway of illustration, the well-known game Tetris may be formed as atwo-dimensional topography in which bodies (e.g., the fallingtetrominoes) move in accordance with predetermined parameters (e.g.,falling at a predetermined speed, and shifting horizontally and/orrotating based on user interaction).

The game instance of the game application 110 may comprise a simulatedvirtual environment, for example, a virtual environment that isaccessible by users via user computing systems 102 that present theviews of the virtual environment to a user. The virtual environment mayhave a topography, express ongoing real-time interaction by one or moreusers and/or include one or more objects positioned within thetopography that are capable of locomotion within the topography. In someinstances, the topography may include a two-dimensional topography. Inother instances, the topography may include a three-dimensionaltopography. The topography may include dimensions of the space and/orsurface features of a surface or objects that are “native” to the space.In some instances, the topography may describe a surface (e.g., a groundsurface) that runs through at least a substantial portion of the space.In some instances, the topography may describe a volume with one or morebodies positioned therein (e.g., a simulation of gravity-deprived spacewith one or more celestial bodies positioned therein). In someembodiments, the instance executed by the computer components may usesynchronous, asynchronous, and/or semi-synchronous architectures.

It should be understood the above description of the manner in whichstate of the virtual environment associated with the video game is notintended to be limiting. The game application may be configured toexpress the virtual environment in a more limited, or richer, manner.For example, views determined for the video game representing the gamestate of the instance of the video game may be selected from a limitedset of graphics depicting an occurrence in a given place within thevideo game. The views may include additional content (e.g., text, audio,pre-stored video content, and/or other content) that describesparticulars of the current state of the place, beyond the relativelygeneric graphics. For example, a view may include a generic battlegraphic with a textual description of the opponents to be confronted.Other expressions of individual places within the video game arecontemplated.

The game application 110 generates game state data 116 that may be usedlocally within the game application and may be transmitted to theinteractive computing system 130 over network 108. The execution of theinstance of the game application 110 may include determining a gamestate associated with the game application. The game state informationmay facilitate presentation of views of the video game to the users onthe user computing systems 102. The game state information may includeinformation defining the virtual environment in which the video game isplayed.

The execution of the game instance may enable interaction by the userswith the game application and/or other users through the interactivecomputing system 130. The game application may be configured to performoperations in the game instance in response to commands received overnetwork 108 from user computing systems 102. In some embodiments, usersmay interact with elements in the video game and/or with each otherthrough the video game.

Users may participate in the video game through client game applicationsimplemented on user computing systems 102 associated with the users.Within the game instance of the video game executed by the state streamgame engine, the users may participate by controlling one or more of anelement in the virtual environment associated with the video game. Theuser-controlled elements may include avatars, user characters, virtualenvironment units (e.g., troops), objects (e.g., weapons, horses,vehicle and so on), simulated physical phenomena (e.g., wind, rain,earthquakes, and/or other phenomena), and/or other user-controlledelements.

The user-controlled avatars may represent the users in the virtualenvironment. The user characters may include heroes, knights,commanders, leaders, generals and/or any other virtual environmententities that may possess strength, skills, abilities, magic powers,knowledge, and/or any other individualized attributes. The virtualenvironment units controlled by the user may include troops and/or anyother game entities that may be trained, recruited, captured, and/orotherwise acquired by the users in groups or en-mass. The objectscontrolled by the users may include weapons, vehicles, projectiles,magic items, wardrobes, boots, armor, knapsacks, medicine, healingpotion, and/or any other virtual items that may be employed by the usersfor interaction within the video game.

The user controlled element(s) may move through and interact with thevirtual environment (e.g., user-virtual environment units in the virtualenvironment, non-user characters in the virtual environment, otherobjects in the virtual environment). The user controlled elementscontrolled by and/or associated with a given user may be created and/orcustomized by the given user. The user may have an “inventory” ofvirtual goods and/or currency that the user can use (e.g., bymanipulation of a user character or other user controlled element,and/or other items) within the virtual environment.

Controls of virtual elements in the video game may be exercised throughcommands input by a given user through user computing systems 102. Thegiven user may interact with other users through communicationsexchanged within the virtual environment. Such communications mayinclude one or more of textual chat, instant messages, private messages,voice communications, and/or other communications. Communications may bereceived and entered by the users via their respective user computingsystems 102. Communications may be routed to and from the appropriateusers through server(s) (e.g., through application host system 132).

Execution and/or performance of the user action by state stream gameengine 112 may produce changes to the game state, which may reflectprogresses and/or results of the user actions. In some examples, statechanges caused by the execution of the user actions may be recorded inthe application data store 106 and/or data store 134 to facilitatepersistency throughout the instance of the video game. In some examples,execution of the user actions may not produce persistent changes to thegame state (e.g., a user character jumping forward and backwardsuccessively may not produce any perceivable game state changes to otherusers).

A given user may input commands with specific parameters to undertakespecific deeds, actions, functions, spheres of actions and/or any othertypes of interactions within the virtual environment. For example, thegiven user may input commands to construct, upgrade and/or demolishvirtual buildings; harvest and/or gather virtual resources; heal virtualuser-controlled elements, non-player entities and/or elements controlledby other users; train, march, transport, reinforce, reassign, recruit,and/or arrange troops; attack, manage, create, demolish and/or defendcities, realms, kingdoms, and/or any other virtual environment locationscontrolled by or associated with the users; craft or transport virtualitems; interact with, compete against or along with non-player entitiesand/or virtual environment elements controlled by other users incombats; research technologies and/or skills; mine and/or prospect forvirtual resources; complete missions, quests, and/or campaigns; exercisemagic power and/or cast spells; and/or perform any other specific deeds,actions, functions, or sphere of actions within the virtual environment.In some examples, the given user may input commands to compete againstelements in an environment within the virtual environment—e.g., Playervs. Environment (PvE) activities. In some examples, the given user mayinput commands to compete against each other within the virtualenvironment—e.g., Player vs. Player (PvP) activities.

The instance of the game application 110 may comprise virtual entitiesautomatically controlled in the instance of the game application. Suchvirtual entities may or may not be associated with any user. As such,the automatically controlled virtual entities may be generated and/ordeveloped by artificial intelligence configured with the gameapplication and/or servers (e.g., application host system(s)) by aprovider, administrator, moderator, and/or any other entities related tothe game application. These automatically controlled entities may evolvewithin the video game free from user controls and may interact with theentities controlled by or associated with the users, other automaticallycontrolled virtual environment entities, as well as the topography ofthe virtual environment. Certain manifested traits may be associatedwith the automatically controlled entities in accordance with theartificial intelligence configured with server(s) (e.g., applicationhost system 132). As used herein, such automatically controlled virtualenvironment entities in the instance of the video game are referred toas “non-player entities.”

In an online game, the instance of the video game may be persistent.That is, the video game may continue on whether or not individual usersare currently logged in and/or participating in the video game. A userthat logs out of the video game and then logs back in some time latermay find the virtual environment and/or the video game has been changedthrough the interactions of other users with the video game during thetime the user was logged out. These changes may include changes to thesimulated physical space, changes in the user's inventory, changes inother users' inventories, changes experienced by non-user characters,and/or other changes.

Embodiments of State Stream Game Engine

FIGS. 2A-2F illustrates an embodiment of the functionality of the statestream game engine 120 in additional detail. In the illustratedembodiment, the state stream game engine 120 comprises the simulationengine 122, the presentation engine 124, and the state stream 126, whichare configured to control the execution and the output of renderedframes for display. Generally, the simulation engine 122 is configuredto execute the game logic of the game application and control the stateof operation. The simulation engine 122 interfaces with the differentstate generating objects of the game application 110 and provides thesimulation and control of the game application 110 based on the variousgame rules and constraints, and inputs received from users. Thesimulation engine 122 responds to inputs provided by the user anddetermines how the game application 110 responds to external inputs aswell as internal inputs within the virtual environment. The simulationengine 122 determines how each virtual object acts and reacts within thegame application. Generally, the CPU of the computing device executesthe functions and processes handled by the simulation engine 122, thoughexecution of the simulation engine 122 is not limited to the CPU. Thepresentation engine 124 is configured to control the output thepresentation of the game application 110 by generating and renderingframes for display on the user computing system 102 or another device.Generally, a GPU of the computing device executes many of the functionsand processes handled by the presentation engine 124, though executionof the presentation engine 124 is not limited to the GPU.

FIG. 2A illustrates an example of an embodiment 200 of execution of thestate stream game engine 120. The state stream game engine provides asystem architecture that provides for the execution of the simulationengine 122 to be decoupled from the execution of the presentation engine124. The simulation engine 122 generates an SSDP and publishes the SSDPto a state stream 126, which may be managed by a state stream manager.The presentation engine 124 reads SSDPs from the state stream 126 togenerate rendered content (e.g., frames) to output. Generally, thesimulation engine 122 does not communicate directly with thepresentation engine 124. Rather, the simulation engine 122 generates anSSDP and writes the SSDP to the state stream 126. The SSDP is generatedand finalized by simulation engine 122 before it is available to thepresentation engine 124 on the state stream 126. After finalization ofthe SSDP, the simulation engine 122 can begin generation of the nextSSDP. The presentation engine 124 can access the SSDP only after theSSDP is written to the state stream. The presentation engine 124 usesthe SSDP to render frames within the game application 110. Thepresentation engine 124 can use any of the SSDPs generated by thesimulation engine 122 in order to generate and render frames. Theexecution of the presentation engine 124 can execute at least one cyclebehind the execution of the simulation engine 122 because the simulationengine 122 must finalize the SSDP before the presentation engine 124 canbegin rendering using the graphical state data included within the SSDP.Some example embodiments of execution of the simulation engine 122 andpresentation engine 124 are further illustrated in FIGS. 2D-2F.

The state stream 126 can be a location in volatile cache memory of theuser computing device 102. The state stream 126 may be a ring buffer ofa defined size within the cache that will continually overwrite SSDPsafter a defined period of time. In some embodiments, as will bedescribed in more detail herein, the game application 110 may havemultiple simulation engines 122 122 operating concurrently, and thepresentation engine 124 can render frames based on the plurality ofSSDP's generated by the plurality of simulation engines 122 122. In suchembodiments, each simulation engine 122 can be associated with adifferent state stream such that each simulation engine 122 is assigneda different logical location in the cache memory for writing SSDPs. Insome embodiments, all the simulation engines 122 may write to a commonstate stream.

The simulation engine 122 generates an SSDP during a simulation cycle,the simulation cycle executes at a rate that is independent of a rate ofa rendering cycle, during which the presentation engine 124 outputs arendered frame of the game application. In the illustrated embodiment,the simulation engine 122 has a simulation cycle of 30 Hz. During eachsimulation cycle, the simulation engine 122 generates and writes an SSDPto the state stream. The presentation engine 124 reads the SSDPs fromthe state stream 126. The rate at which the presentation engine 124renders frames can be greater than the rate at which the simulationengine 122 generates SSDPs. The presentation engine 124 can interpolatethe SSDPs in order to render frames at a faster rate than the rate atwhich the SSDPs are generated by the simulation engine 122. Someexamples of rendering and interpolation are illustrated in FIGS. 2D-2F.Although in the illustrated example, the simulation engine 122 isrunning at a fixed rate and the presentation engine 124 is running at avariable rate, the simulation engine 122 and/or the presentation engine124 can execute at a fixed or variable rate. The SSDP's can be generatedat any frequency as defined by the game application and/or the hardwarecomputing resources of the interactive computing system servers and/orthe client computing devices. For example, the SSDP's could be generatedat 10, 15, 30, 40, 60, 120 Hz, or any other time period. In someembodiments, the simulation cycle may have a variable rate.

With additional reference to FIGS. 2B and 2C, the embodiment 200 of thestate stream game engine 120 is illustrated with additional detail. Asillustrated, the simulation engine 122 can generates discrete SSDPsduring runtime of the game application, which are illustrated by blocksS0, S1, S2, and so on. The SSDPs are written to the state stream 126 bythe simulation engine 122. In some embodiments, the SSDP may be writtenas a complete block to the state stream 126 or may be written piecemealto the state stream. In either case, The SSDP is not available to thepresentation engine 124 on the state stream until the SSDP is completeand made available to the presentation engine 124. After an SSDP isavailable, the presentation engine 124 then reads the SSDP from thestate stream 126. Generally, communication of the simulation engine 122and the presentation engine 124 with the state stream is aone-directional. The simulation engine 122 writes to the state streamand the presentation engine 124 reads from the state stream. Thesimulation engine 122 and presentation engine 124 can operate indifferent threads. In this manner, the simulation engine 122 can runindependent of each other. As long as the presentation engine 124 lagsbehind the generation of SSDP by the simulation engine 122, then thepresentation engine 124 can continue to render without waiting for thegeneration of the next SSDP. Additionally, since each SSDP contains allthe state necessary for rendering, the presentation engine 124 does nothave to wait for the computation and generation of state values forindividual state stream processes within the SSDP. As illustrated inFIG. 2C, each SSDP is composed of a plurality of individual state streamprocesses that are generated during each simulation cycle. Thegeneration of the state stream processes are added to the SSDP, andafter all the state stream processes have been completed, the SSDP willbe finalized and available on the state stream. In some embodiments, theSSDP will be written at a defined rate, such as at 30 Hz. Asillustrated, when the cycle is completed and the SSDP is finalized(e.g., S0), the simulation engine 122 can begin generation of the nextSSDP (e.g., S1).

The state stream processes comprise the state generating objects withinthe game application that need to be provided to the presentation engine124 in order for the presentation engine 124 to have the stateinformation necessary to generate the render state of the game at thepoint in time that the SSDP is generated. FIG. 2C provides anabbreviated list of example state stream processes that may be includedin an SSDP, such as, LensFlare, OccluderMesh, OccluderPlane,OccluderVolume, RenderVolume, GroundHeight, and so forth. Generally, allgame systems within a game application can go through state stream. Forexample, some games systems executed within the game application caninclude Models, Emitters, Lights, Visual environments, and others. Thegraphical state data generated for state stream processes can differfrom the simulation state data in that, the graphical state dataincludes a subset of the state necessary for the presentation engine 124to regenerate the graphical virtual environment at the time thatgraphical state data was generated. The graphical state data can be afiltered version of the simulation state data associated with thevirtual objects that include less than all of the state that is requiredto execute the game. For each state stream process of a virtual object,the graphical state data can include static state information anddynamic state information. Static state information refers to stateinformation that is the same for the entire life of an object. Dynamicstate information refers to state information that changes over the lifeof an object. The full graphical state of an object at time X (that is,the time at which the SSDP is generated) is the static state informationin conjunction with the interpolated dynamic state information.

As discussed, the state data provided by the simulation engine 122 tothe state stream 126 is a subset of the simulation state data associatedwith a virtual object. The graphical state data included in a statestream process provides the state data necessary for the presentationengine 124 to generate the graphical state of the game at particularpoint in time. The graphical state data can provide static and dynamicstate information such as locations, transforms, and any necessaryinformation for the presentation engine 124 to recreate the virtualenvironment at a particular point in time. The state of the virtualenvironment is frozen in time when the state stream processes aregenerated for an SSDP. The presentation engine 124 is capable of usingthe state information provided within an SSDP to recreate at least aportion of the virtual environment of the game application at the pointin time, similar to a freeze frame or screenshot of the virtualenvironment. In some embodiments, the SSDP may provide a default pointof view for generating and rendering the frame (e.g., the player'sperspective within the game application). However, the SSDP providessufficient graphical state data for the recreation of the graphicalstate of the virtual environment at the point in time of the SSDP andthe generation of the graphical state at the time is not limited to asingle perspective within the game application (e.g., the player'sperspective). The SSDP can provide the state data required to recreatethe virtual environment from any angle or camera perspective. Thisallows the presentation engine 124 to generate and render a frame of thegraphical state from any angle or position within the virtualenvironment, or portion thereof, based on the graphical state data. Forexample, an action within the game may trigger the creation of framesfrom a different perspective than the player's default point of view.

As an illustrative example of graphical state data, a wheel on a movingcar within an instance of the virtual environment may include staticstate data used for identifying unchanging characteristics (such as, themesh and skin of the wheel), and the dynamic state data identifyingchanging characteristics of the wheel (such as, location of the wheelwithin the virtual environment and rotation of the wheel about a centeraxis). The graphical state data of the wheel does not need to includedata that is relevant to the simulation of the game, such as the speedof the rotation of the wheel or the speed at which the car is travellingwithin the virtual environment, but is not relevant or does not affectthe rendering of the wheel within the game application. In this example,the ‘frozen’ state of the wheel would be provided as graphical statedata for the wheel state stream process within the SSDP and then writtento the state stream. The presentation engine 124 can then use thegraphical state data provided within the SSDP to render a frame. Thegenerated frame may or may not include a rendering of the wheel.However, the graphical state data for the wheel would be included withinthe SSDP in order for the presentation engine 124 to generate the gameenvironment and render a frame from a perspective that would include thewheel in the correct position.

In some embodiments, the graphical state data that is generated for eachstate stream process can be stored as a difference between the currentSSDP and the previous SSDP. The state values of each of the variousstate variables within the game can be stored as a struct that maintainsthe state values for an object. In this manner, the simulation engine122 can determine what the state of an object at any point during thesimulation.

In some embodiments, the presentation engine 124 can maintain a copy ofthe current graphical state data generated by the simulation engine 122.The simulation engine 122 may be configured to only write state valuesthat have changed from the previous state to the SSDP. The presentationengine 124 can use the graphical state data received from the SSDP toupdate the current graphical state of the virtual environment. In thismanner, the size of SSDP can be significantly reduced as compared togenerating an entire copy of the graphical state data for the currentgraphical state of the virtual environment. This can also reduce theamount of time that is required for the simulation engine to generateand finalize an SSDP.

With additional reference to FIGS. 2D-2F, various embodiments of thetiming and synchronization of the simulation engine 122 and presentationengine 124 are illustrated. The independence of the execution of thesimulation engine 122 and presentation engine 124 provide for aplurality of the different modes of operation of the state stream gameengine. FIGS. 2D-2F provide examples of instances of execution of thesimulation and rendering cycles. The examples are not limiting andmerely provides illustrative examples for executing the state streamgame engine. The presentation engine 124 can render frames byinterpolation between the previous two SSDPs generated by the simulationengine 122 (e.g., S0 and S1). The illustrated examples provide examplesof how the simulation engine 122 and presentation engine 124 executeduring a simulation cycle. In the illustrated examples, the presentationengine 124 is executing rendering cycles at 180 Hz and the simulationengine 122 is executing simulation cycles at 30 Hz, which results in sixrendering cycles for each simulation cycle.

The presentation engine 124 can render a plurality of frames based oneach SSDP. The presentation engine 124 can run at a faster cycle timethan the simulation engine 122. For example, the simulation engine 122may be operating at 30 Hz and the presentation engine 124 is renderingframes at a greater rate (e.g., 180 Hz). The presentation engine 124will need to generate multiple frames to output to the display betweeneach generation of a SSDP. For example, if the simulation engine 122generates an SSDP at each simulation cycle at 30 Hz and the presentationengine 124 renders frames at 120 FPS, then the presentation engine 124would need to generate 4 frames per simulation cycle, or in other wordsexecute four rendering cycles per simulation cycle. The presentationengine 124 can use a previous SSDP (e.g., S0) and the current state (S1)in order to determine interpolation of the graphical states of thevirtual environment. In some embodiments, the presentation engine canlag behind the simulation current cycle by more than one cycle. Forexample, the presentation can use S0 and S1 for generation of frameseven though the current cycle is S4.

The presentation engine 124 does not write or change the values of thestates of the graphical state data that is written to the state streamby the simulation engine 122. The presentation engine 124 can performfunctions of cleaning up SSDPs after they have been consumed by thepresentation engine 124 and are no longer needed. Once the presentationengine 124 has fully consumed a state, or if a state was never used, thestate can be deleted from the state stream, or flagged for deletion oroverwriting.

FIG. 2D illustrates an embodiment in which the simulation engine 122generates and finalizes an SSDP at the end of the simulation cycle, suchthat S2 is completed just prior to the end of the sixth rendering cycle.If generation of the SSDP takes the entire simulation cycle to complete.After the simulation engine 122 completes the SSDP (S2), simulationengine 122 immediately begins the next SSDP (S3). The presentationengine 124 can continue to render frames without 1 as long as the SSDPcompletes prior to the end of the sixth rendering cycle. In thisembodiment, there is no buffer between the time that the SSDP iscompleted and the rendering for the next rendering cycle needs tocommence. In which case, if the finalization of the SSDP is delayed, thenext rendering cycle can be delayed as well.

FIG. 2E illustrates an embodiment in which the simulation engine 122generates and finalizes an SSDP prior to the end of the simulationcycle, such as in 5.5 milliseconds of the total 33 millisecondsallocated to the simulation cycle time. Since generation of the SSDPtakes only a portion of the simulation cycle to complete, the simulationengine 122 can dedicate processing resources to other processes, such asrendering prior to initiation of the next SSDP (S3). At the beginning ofthe next simulation cycle, the simulation engine can generate the nextSSDP. The length of time the simulation engine takes to generate theSSDP may differ based on the simulation of the game. For example, moredynamic simulation processes where many state values are changing canresult in the generation of SSDPs at a slower rate (such as illustratedin FIG. 2D) than compared to when a user is in a menu selection screenwithin the simulation of the game application 110.

FIG. 2F illustrates an embodiment in which the simulation engine 122generates and finalizes an SSDP prior to the end of the simulationcycle, such that S2 is completed with a buffer of time prior to the endof the sixth rendering cycle. Generation of the SSDP takes only aportion of the simulation cycle to complete. After the simulation engine122 completes the SSDP (S2), simulation engine 122 can dedicateprocessing resources to other processes, such as rendering prior toinitiation of the next SSDP (S3). In this embodiment, the simulationengine has a variable simulation cycle and the simulation engine beginsgenerating an SSDP that does not follow a fixed simulation cycleduration. The SSDP can include the time that the simulation cycle tookto complete the SSDP. This information can be used by the presentationto predict the number of rendering cycles between simulation cycles.This can be also be used when the simulation cycle takes longer than thedetermined simulation cycle time. For example, if the creation of theSSDP took 55 milliseconds, the presentation engine can predict that themore rendering cycles will need to be completed prior to receiving thenext SSDP. In such a case, the presentation can adjust the interpolationof the SSDPs and the number of rendering cycles based on the prediction.

State Stream Game Engine with Replay Functionality

FIG. 3 illustrates a block diagram 300 of a state stream game enginethat includes replay functionality. In the illustrated embodiment, thereplay functionality can be implemented by writing the SSDPs to thestate stream and to storage simultaneously. Generally, after the stateis consumed by the presentation engine 124, it is removed from the statestream and no longer available to use for rendering by the presentationengine 124. However, the SSDP can be persistently saved by having thesimulation engine 122 simultaneously write to a storage location, suchas non-volatile memory, on the computing device. The storage locationcan be written to a different location on the computing device than whatis designated and allocated for the state stream. The presentationengine 124 can load the states from the disk to the state stream inorder to consume the states again. In the illustrated example, the SSDPis being written from the storage to a second state stream. Thoughillustrated as a second state stream, the first state stream and thesecond state stream may be the same allocated memory location on thecomputing device. In some embodiment, the state stream game engine mayhave different state streams with different allocated memory locations.

The SSDPs written to memory may be used for replaying the sequences of agameplay session. For example, if a user wanted to watch a replay ofhighlights of a game, the SSDPs associated with the requested sequenceof events could be written from storage into state stream. Thepresentation engine 124 could generate and render the frames for theSSDPs in order to display a replay to the user. The data could bedisplayed in the same manner and angle that was originally provided tothe user during gameplay of the game, such as a goal in a soccer game.Additionally, the state data includes the state data necessary for thepresentation engine 124 to recreate the virtual scene within the gameapplication, the presentation engine 124 can render the replay from adifferent perspective or point of view within the game environment. Forexample, the replay may provide the replay of a goal scored by theplayer, which can be displayed from the goal scorer's point of view, thegoal keeper's point of view, a bird's eye point of view, or any otherpoint of view. The recreation of the scene can be controlled by adisplay manager of the presentation engine 124. In some embodiments, thesimulation engine may generate a display manager SSDP that can be usedby the presentation engine to determine the point of view that is beingoutput for display. For example, during gameplay the display managerSSDP can provide instructions for the presentation engine to use theSSDP from state stream A and during a replay, the display manager SSDPcan provide instructions for the presentation engine to use the SSDPfrom state stream B.

The SSDPs written to storage during the gameplay session may be storedin a ring buffer. The ring buffer may cycle through a defined amount ofgameplay time, such as 10 minutes, 15 minutes, or another amount ofdefined time. Some of the SSDPs can be flagged so that they are notoverwritten when the ring buffer cycles through. The SSDPs may beflagged based on specific events that occurred during gameplay, such asscoring a goal, or based on other criteria defined by the specific rulesand parameters of the game application. Generally, after an SSDP isconsumed, the presentation engine 124 manages the removal of the SSDPfrom the state stream. In the case of SSDPs that are written into thestate stream from storage, the SSDP may be rewritten into storage or notremoved from storage when written into the state stream prior toconsumption by the presentation engine 124.

In some embodiments, the presentation engine 124 can utilize multipledifferent SSDPs to generate and render a frame. The presentation engine124 may pull state information from any number of states in order togenerate a frame. For example, the presentation engine 124 may generatea series frames by combining multiple states together to create acollage of graphics generated from multiple different states.

State Stream Game Engine with Multiple Simulation engines 122

FIG. 4 illustrates a block diagram 400 of a state stream game enginethat includes multiple simulation engines 122. In the illustratedembodiment, the multiple simulation engines 122 can generate stateinformation simultaneously. The multiple simulation engine 122′s may begenerating SSDPs for different aspects of a video game. For example, afirst simulation engine 122 may be configured to generate state for afirst virtual character in a first virtual environment (e.g., a firstvirtual world) within the game application. The second simulation engine122 can be configured to generate state for a second virtual characterin a second virtual environment (e.g., a second virtual world) withinthe game application. The independent state engines can independentlydetermine the state associated with each virtual world, which may begoverned by different rules of operation and constraints within the gameapplication. For example, the game application may have a persistentvirtual environment that continues to execute independent of the virtualcharacters within the persistent virtual environment. As illustrated,each simulation engine 122 can write the SSDPs to a state streamallocated for the simulation engine 122. In some embodiments, the statestream game engine may have a common state stream for all simulationengines 122.

The presentation engine 124 can use the data to generate frames thatincludes state information from multiple simulation engines 122. As anillustrative example, the game application may generate frames thatinclude state information received from a first virtual character in afirst virtual environment (with SSDPs generated by a first simulationengine 122) and from a second virtual character in a second virtualenvironment (with SSDPs generated by a second simulation engine 122). Inthis example, the game application may include persistent virtualenvironments in which the state continues to generate regardless ofwhether the user is actively playing either the first or second virtualcharacter. The user may select to view only one character, in whichcase, the SSDPs from simulation engine 1221 or simulation engine 1222would be used to generate frames for display to the user. The user maychoose to have a picture in picture view of the second character whilethe first character is active or visa-versa. The presentation engine 124can then use the SSDPs from simulation engine 1221 and simulation engine1222 to generate the frame. In some embodiments, one or more of thesimulation engine may generate a display manager SSDP that can be usedby the presentation engine to determine the point of view that is beingoutput for display. The presentation engine 124 can be responsible fordisposing of consumed and or unused SSDPs within a state stream.

In some embodiments, the different simulation engines 122 may begenerated on different computing systems. The simulation engine 122 canthen send the SSDP to another computing system over a network. In such acase, the latency of the network connection would need to be factoredinto the timing and transmission of the SSDP between computing devices.In an illustrative example, in a competitive gaming environment, eachcomputing system associated with a player may send SSDPs, generated bytheir simulation engine 122, to an announcer computing system. Thepresentation engine 124 of the announcer computing system can be adifferent type of presentation engine 124 that the player computingsystems. The announcer presentation engine 124 may be configured to havedifferent functionality and/or display options for controlling and/orgenerating frames that contain graphical state information received fromthe respective SSDPs. The announcer computing system may also include adifferent simulation engine 122 specific to the announcer computingsystem in order to execute a different type of application than theplayer computing systems.

In some embodiments, a game application may stop or suspend operation ofsimulation engines 122 during execution of the game application. Themultiple simulation engines 122 may be executed in series or in inparallel based on the functionality and/or constraints of the gameapplication. Prior to stopping operation of a simulation engine 122, asimulation engine 122 can generate SSDPs that can be configured to beused at different times within the game application. Depending on whatis being presented by the presentation engine 124 (such as, aprerendered cut scene), the simulation engine 122 may have the budget togenerate additional SSDPs that are not intended to be displayed as theygenerated. Rather, these SSDPs can be written to storage. These SSDPscan be used for the generation of frames at another point in time andunder different conditions. For example, the state that is beinggenerated for the presentation engine 124 to be displayed at a differenttime(s) within the game application. In one embodiment, when asimulation engine 122 is going to be terminated, the simulation engine122 can generate a number of SSDPs that are determined to be used withina game after the new simulation engine 122 is being implemented. Forexample, a simulation engine 122 (SE1) may generate SSDPs for thedestruction of a virtual planet controlled by simulation engine 1221.When the user transitions to a new virtual planet, which is controlledby a new simulation engine 122 (SE2), the SSDPs associated withdestruction of the virtual planet may be used by presentation engine 124to generate frames displaying the destruction of the virtual planet,even though simulation engine 1221, which generated the SSDPs, is nolonger executing.

The execution of multiple simulation engines 122 and preparation ofSSDPs provides for a presentation engine 124 to operate completelyindependent and decoupled from the operations of the simulation engine122. The presentation engine 124 can generate and render frames based onstate information received from any SSDP regardless of whether thesimulation engine 122 is currently executing or executing on the samecomputing system as the presentation engine 124. Additionally, thepresentation engine 124 generating and rendering frames can be adifferent type of presentation engine 124 with different functionalitythan the presentation engine 124 that is being used on computing systemsthat is playing the game application and generating the SSDPs.

State Stream Game Engine for Multiplayer Game Application

FIG. 5 illustrates a block diagram 500 of a state stream game enginethat is executing in a multiplayer game application environment wherethe execution of the state of each client computing system within thesimulation of the game application is synchronized. The synchronizationof the game application requires that each client computing device isoperating on the same simulation clock and each is executing the sametime cycle at the same time. In such an embodiment, the behavior of thegeneration of the SSDPs by the simulation engines 122 may not begenerated when the client computing device completes the simulationcycle. Rather, the SSDP is only generated after certain criteria aresatisfied. For example, an SSDP may not be finalized until the serverreceives input from each player (through their client computing system)participating in a multiplayer game. In some embodiments, the simulationengine 122 will only generate the SSDPs when each of the client systemshas provided their input to the simulation engine 122 and the simulationengine 122 receives an indication from the server that the cycle iscomplete. In instances where there is peer-to-peer communication (suchas, a two player game), the simulation engine 122 may not proceed untilthe input is received from the other player. In such embodiments, thesimulation can be heavily dependent upon network latencies, as eachplayer's simulation is dependent on the highest latency client. This canhave a significant effect on the quality of gameplay within the game.The game application may have thresholds the govern what happens whenthe latency of a client is too great and is adversely affecting thesimulation. For example, when one of the players has a network latencythat is too high, the player may be kicked out of the game.Additionally, in these embodiments, the network connections can resultin periods of high and low latency, which can result in bursts of SSDPsthat are generated. In order to accommodate the aperiodic nature of thegeneration of the SSDPs, the presentation engines can be configured sothat the rendering of frames is based on frames that are more than onecycle behind the simulation cycle. The number of cycles can be based onthe predicted latencies, the game application and other factors. Bylagging behind a plurality of cycles, the presentation engine canprovide rendered frames at a consistent rate without being affected bythe inconsistent generation of simulation cycles.

State Stream Execution Processes

FIGS. 6A-6B and 7A-7B illustrate embodiments of flowcharts for executingprocesses of a state stream game engine within a game application. Theprocesses, in whole or in part, can be implemented by CPUs and/or GPUsconfigured with computer readable instructions to execute a gameapplication. For example, the process, in whole or in part, can beimplemented by the game application, state stream game engine,simulation engine 122, state stream, and/or the presentation engine 124.Although any number of systems, in whole or in part, can implement theprocesses, to simplify discussion, the processes will be described withrespect to the game application, state stream game engine, simulationengine 122, state stream, and/or the presentation engine 124.

Simulation Engine Execution Process

FIG. 6A illustrates an embodiment of a process 600 for execution of asimulation engine 122 during a simulation cycle within the state streamgame engine.

At block 602, a simulation engine 122 initiates a new SSDP for asimulation cycle. The new SSDP can be initiated immediately after aprevious SSDP (such as, illustrated in FIG. 2D), or there may be a timeperiod between the previous SSDP and the new SSDP (such as, illustratedin FIGS. 2E-2F). The simulation cycle can be configured to occur on aperiodic basis (such as, every 30 Hz), an aperiodic basis (such as, assoon as the previous cycle completed), or based on requirements of thegame application (such as, after receiving input from other usercomputing devices in a multiplayer game).

At block 604, the simulation engine 122 generates state data for atleast a portion of the virtual objects within the simulation. During thesimulation cycle, the simulation engine can generate new state data forvirtual objects within the virtual objects. The simulation may onlygenerate state data for virtual objects where the state data changed inthe current simulation cycle compared to the previous simulation cycle.In some embodiment, state data for all virtual objects are generated ineach simulation cycle. The simulation engine may only generate statedata that is associated with a portion of the virtual environment. Forexample, in an online game, the simulation engine may only have accessto a portion of the total state data associated with the virtualenvironment.

At block 606, the simulation engine 122 generates graphical state datafor state stream processes that are necessary for presentation engine124 to render virtual objects within the virtual environment. Thegraphical state data can be a subset of the simulation state data. Thesimulation engine may not generate any data for state stream processwhere the state did not change when compared to the previous simulationstate.

At block 608, the simulation engine writes the graphical state data tothe SSDP. The graphical state data for state stream process can bewritten to the SSDP as soon as the graphical state data is generated.

At block 610, the simulation engine 122 finalizes the SSDP and makes theSSDP available to the presentation engine on the state stream. Thesimulation engine may write the SSDP to the state stream as a singleblock or may write to the state stream during the simulation cycle andnot finalize or otherwise make the SSDP available until the SSDP iscomplete. The finalized SSDP can be written to the state stream at thetime designated by the timing of the simulation cycle. The state streamcan be a location in volatile cache memory that is allocated for thesimulation engine 122. The write can be one-directional, from thesimulation engine 122 to the state stream. In some embodiments, the SSDPcan have a defined time period in which to generate and write the SSDPto the state stream. The SSDP may be completed prior to the end of asimulation cycle. For example, a SSDP may be completed halfway throughthe simulation cycle.

At block 612, optionally, the simulation engine 122 writes the SSDP toan allocated storage location, simultaneously with the SSDP written tothe state stream. The allocated storage location may be located innon-volatile storage on a storage device. After the write is complete,the process returns to block 602

Presentation Engine Execution Process

FIG. 6B illustrates an embodiment of a process 650 for execution of apresentation engine 124 within the state stream game engine.

At block 652, the presentation engine 124 reads at least one SSDP fromthe state stream for a new rendering cycle. The read is one-directional.The presentation engine 124 does not write modify the graphical statedata included in the SSDP. The presentation engine 124 does not readdata directly from the simulation engine 122.

At block 654, the presentation engine can update the current graphicalstate of the virtual environment based on the SSDP. The presentationengine can maintain the current graphical state of each virtualenvironment. Based on the SSDP, the presentation engine can then updatethe current state based on the state values that were changed andprovided by the SSDP.

At block 656, the presentation engine 124 uses the SSDP (SSDP1) and aprevious SSDP (SSDP0) to determine interpolation for rendering of framesbased at least in part on a rendering frame rate and a simulation cycletime period. When the simulation cycle occurs at a defined periodicity,the presentation engine 124 can determine the interpolation calculationsbased on the calculated frame rate. The presentation engine can predictthe number of rendering cycles based on a predicted or definedsimulation rate and the predicted or defined frame rate.

At block 658, the presentation engine 124 renders frames based ondetermined interpolation. The frames can be rendered using the graphicalstate data from SSDP1 and SSDPO. In some embodiments, graphical statedata can be used from more than one SSDP in order to render one or moreframes. In some embodiments, the presentation engine may use SSDPs forrendering that are a plurality of states behind a current state. Thepresentation engine 124 can generate and render frames using the SSDPswithout any interaction or dependencies to the simulation engine 122.

At block 660, after the rendering cycle is complete and the SSDP is nolonger needed from the state stream, the presentation engine 124 canclean up or otherwise tend to the disposal of the SSDP. The presentationengine 124 may delete one or more SSDPs from state stream. In someembodiments, the presentation engine 124 may delete SSDPs that wereconsumed and/or SSDPs that were not consumed, but are no longer needed.In some embodiments, the state stream is a ring buffer, and thepresentation engine 124 flags SSDPs within the ring buffer that can beoverwritten. After the rendering cycle is complete, the process returnsto block 652.

Execution Process for Multiple Simulation Engines 122

FIG. 7A illustrates an embodiment of a process 700 for execution ofmultiple simulation engines 122 during a simulation cycle within thestate stream game engine.

At block 702, a plurality of simulation engines 122 initiate new SSDPsfor a simulation cycle. The simulations cycles for each simulationengine 122 may be synchronized or may be out of synchronization. Eachsimulation engine 122 runs completely independently of the othersimulation engines 122. There may be no execution dependencies betweenthe simulation engines 122. Each simulation engine 122 can generate anSSDP without input from another simulation engine 122. The new SSDP canbe initiated immediately after a previous SSDP (such as, illustrated inFIG. 2D), or after a time period between the previous SSDP and the newSSDP (such as, illustrated in FIGS. 2E-2F). The simulation cycle can beconfigured to occur on a periodic basis (such as, every 30 Hz), anaperiodic basis (such as, as soon as the previous cycle completed), orbased on requirements of the game application (such as, after receivinginput from other user computing devices in a multiplayer game). At leastone of the simulation engines may be configured to generate a displaymanager SSDP that includes data indicating how to combine the graphicalstate data from the various SSDPs for rendering a frame.

At block 704, each simulation engine 122 generates state data for atleast a portion of the virtual objects within the simulation. During thesimulation cycle, the simulation engine can generate new state data forvirtual objects within the virtual objects. The simulation may onlygenerate state data for virtual objects where the state data changed inthe current simulation cycle compared to the previous simulation cycle.In some embodiment, state data for all virtual objects are generated ineach simulation cycle. The simulation engine may only generate statedata that is associated with a portion of the virtual environment. Forexample, in an online game, the simulation engine may only have accessto a portion of the total state data associated with the virtualenvironment.

At block 706, each simulation engine 122 generates graphical state datafor state stream processes that are necessary for presentation engine124 to render virtual objects within the virtual environment. Thegraphical state data can be a subset of the simulation state data. Thesimulation engine may not generate any data for state stream processwhere the state did not change when compared to the previous simulationstate.

At block 708, each simulation engine writes the graphical state data tothe SSDP. The graphical state data for state stream process can bewritten to the SSDP as soon as the graphical state data is generated.

At block 710, each simulation engine 122 finalizes the SSDP and makesthe SSDP available to the presentation engine on the state stream. Thesimulation engine may write the SSDP to the state stream as a singleblock or may write to the state stream during the simulation cycle andnot finalize or otherwise make the SSDP available until the SSDP iscomplete. The finalized SSDP can be written to the state stream at thetime designated by the timing of the simulation cycle. The state streamcan be a location in volatile cache memory that is allocated for thesimulation engine 122. The write can be one-directional, from thesimulation engine 122 to the state stream. In some embodiments, the SSDPcan have a defined time period in which to generate and write the SSDPto the state stream. The SSDP may be completed prior to the end of asimulation cycle. For example, a SSDP may be completed halfway throughthe simulation cycle.

At block 712, optionally, the simulation engine 122 writes the SSDP toan allocated storage location, simultaneously with the SSDP written tothe state stream. The allocated storage location may be located innon-volatile storage on a storage device. After the write is complete,the process returns to block 702

Execution Process for Presentation Engine with Multiple SimulationEngines

FIG. 7B illustrates an embodiment of a process 750 for execution of apresentation engine 124 interfacing with multiple simulation engines 122within the state stream game engine.

At block 752, the presentation engine 124 identifies a plurality ofSSDPs from one or more state streams for a new rendering cycle. Thepresentation engine 124 does not write to the state stream. Thepresentation engine 124 does not read data directly from the simulationengine 122. The presentation engine 124 reads multiple SSDPs fromdifferent simulation engines 122. In some embodiments, the presentationengine reads a display manager SSDP that includes data indicating how tocombine the graphical state data from the various SSDPs for rendering aframe.

At block 754, the presentation engine can update the current graphicalstate of each virtual environment based on the SSDPs. The presentationengine can maintain the current graphical state of each virtualenvironment. Based on the SSDPs, the presentation engine can then updatethe current state based on the state values that were changed andprovided by the SSDPs.

At block 756, the presentation engine 124 uses the multiple SSDPs and aprevious SSDPs to determine interpolation for rendering of frames basedat least in part on a rendering frame rate and a simulation cycle timeperiod. When the simulation cycle occurs at a defined periodicity, thepresentation engine 124 can determine the interpolation calculationsbased on the calculated frame rate. The presentation engine can predictthe number of rendering cycles based on a predicted or definedsimulation rate and the predicted or defined frame rate.

At block 758, the presentation engine 124 renders frames based ondetermined interpolation and the current states of the virtualenvironments. The frames can be rendered using the graphical state datafrom the plurality of SSDPs from each of the simulation engines 122. Thegraphical state data can be used to create a frame for rendering fromthe plurality of SSDPs. In some embodiments, based on presentationparameters within the game application, only graphical state data fromone of the SSDPs are used to generate and render a frame. Thepresentation engine 124 can generate and render frames using the SSDPswithout any interaction or dependencies to the simulation engines 122.In some embodiments, the presentation engine can use data received froma display manager SSDP to determine how to use the generate the framesbased on the current states of each virtual environment.

At block 760, after the rendering cycle is complete and the SSDP is nolonger needed from the state stream, the presentation engine 124 canclean up or otherwise tend to the disposal of the SSDP(s). Thepresentation engine 124 may delete one or more SSDPs from state stream.In some embodiments, the presentation engine 124 may delete SSDPs thatwere consumed and/or SSDPs that were not consumed, but are no longerneeded. In some embodiments, the state stream is a ring buffer, and thepresentation engine 124 flags SSDPs within the ring buffer that can beoverwritten. After the rendering cycle is complete, the process returnsto block 752.

Overview of Computing Device

FIG. 8 illustrates an embodiment of computing device 10 according to thepresent disclosure. Other variations of the computing device 10 may besubstituted for the examples explicitly presented herein, such asremoving or adding components to the computing device 10. The computingdevice 10 may include a game device, a smart phone, a tablet, a personalcomputer, a laptop, a smart television, a car console display, a server,and the like. As shown, the computing device 10 includes a processingunit 20 that interacts with other components of the computing device 10and also external components to computing device 10. A media reader 22is included that communicates with media 12. The media reader 22 may bean optical disc reader capable of reading optical discs, such as CD-ROMor DVDs, or any other type of reader that can receive and read data fromgame media 12. One or more of the computing devices may be used toimplement one or more of the systems disclosed herein.

Computing device 10 may include a separate graphics processor 24. Insome cases, the graphics processor 24 may be built into the processingunit 20. In some such cases, the graphics processor 24 may share RandomAccess Memory (RAM) with the processing unit 20. Alternatively, or inaddition, the computing device 10 may include a discrete graphicsprocessor 24 that is separate from the processing unit 20. In some suchcases, the graphics processor 24 may have separate RAM from theprocessing unit 20. Computing device 10 might be a handheld video gamedevice, a dedicated game console computing system, a general-purposelaptop or desktop computer, a smart phone, a tablet, a car console, orother suitable system.

Computing device 10 also includes various components for enablinginput/output, such as an I/O 32, a user I/O 34, a display I/O 36, and anetwork I/O 38. I/O 32 interacts with storage element 40 and, through adevice 42, removable storage media 44 in order to provide storage forcomputing device 10. Processing unit 20 can communicate through I/O 32to store data, such as game state data and any shared data files. Inaddition to storage 40 and removable storage media 44, computing device10 is also shown including ROM (Read-Only Memory) 46 and RAM 48. RAM 48may be used for data that is accessed frequently.

User I/O 34 is used to send and receive commands between processing unit20 and user devices, such as game controllers. In some embodiments, theuser I/O can include a touchscreen inputs. The touchscreen can becapacitive touchscreen, a resistive touchscreen, or other type oftouchscreen technology that is configured to receive user input throughtactile inputs from the user. Display I/O 36 provides input/outputfunctions that are used to display images from the game being played.Network I/O 38 is used for input/output functions for a network. NetworkI/O 38 may be used during execution of a game.

Display output signals produced by display I/O 36 comprising signals fordisplaying visual content produced by computing device 10 on a displaydevice, such as graphics, user interfaces, video, and/or other visualcontent. Computing device 10 may comprise one or more integrateddisplays configured to receive display output signals produced bydisplay I/O 36. According to some embodiments, display output signalsproduced by display I/O 36 may also be output to one or more displaydevices external to computing device 10, such a display 16.

The computing device 10 can also include other features that may be usedwith a game, such as a clock 50, flash memory 52, and other components.An audio/video player 56 might also be used to play a video sequence,such as a movie. It should be understood that other components may beprovided in computing device 10 and that a person skilled in the artwill appreciate other variations of computing device 10.

Program code can be stored in ROM 46, RAM 48 or storage 40 (which mightcomprise hard disk, other magnetic storage, optical storage, othernon-volatile storage or a combination or variation of these). Part ofthe program code can be stored in ROM that is programmable (ROM, PROM,EPROM, EEPROM, and so forth), part of the program code can be stored instorage 40, and/or on removable media such as game media 12 (which canbe a CD-ROM, cartridge, memory chip or the like, or obtained over anetwork or other electronic channel as needed). In general, program codecan be found embodied in a tangible non-transitory signal-bearingmedium.

Random access memory (RAM) 48 (and possibly other storage) is usable tostore variables and other game and processor data as needed. RAM is usedand holds data that is generated during the execution of an applicationand portions thereof might also be reserved for frame buffers,application state information, and/or other data needed or usable forinterpreting user input and generating display outputs. Generally, RAM48 is volatile storage and data stored within RAM 48 may be lost whenthe computing device 10 is turned off or loses power.

As computing device 10 reads media 12 and provides an application,information may be read from game media 12 and stored in a memorydevice, such as RAM 48. Additionally, data from storage 40, ROM 46,servers accessed via a network (not shown), or removable storage media46 may be read and loaded into RAM 48. Although data is described asbeing found in RAM 48, it will be understood that data does not have tobe stored in RAM 48 and may be stored in other memory accessible toprocessing unit 20 or distributed among several media, such as media 12and storage 40.

It is to be understood that not necessarily all objects or advantagesmay be achieved in accordance with any particular embodiment describedherein. Thus, for example, those skilled in the art will recognize thatcertain embodiments may be configured to operate in a manner thatachieves or optimizes one advantage or group of advantages as taughtherein without necessarily achieving other objects or advantages as maybe taught or suggested herein.

All of the processes described herein may be embodied in, and fullyautomated via, software code modules executed by a computing system thatincludes one or more computers or processors. The code modules may bestored in any type of non-transitory computer-readable medium or othercomputer storage device. Some or all the methods may be embodied inspecialized computer hardware.

Many other variations than those described herein will be apparent fromthis disclosure. For example, depending on the embodiment, certain acts,events, or functions of any of the algorithms described herein can beperformed in a different sequence, can be added, merged, or left outaltogether (for example, not all described acts or events are necessaryfor the practice of the algorithms). Moreover, in certain embodiments,acts or events can be performed concurrently, for example, throughmulti-threaded processing, interrupt processing, or multiple processorsor processor cores or on other parallel architectures, rather thansequentially. In addition, different tasks or processes can be performedby different machines and/or computing systems that can functiontogether.

The various illustrative logical blocks and modules described inconnection with the embodiments disclosed herein can be implemented orperformed by a machine, such as a processing unit or processor, adigital signal processor (DSP), an application specific integratedcircuit (ASIC), a field programmable gate array (FPGA) or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described herein. A processor can be a microprocessor, but inthe alternative, the processor can be a controller, microcontroller, orstate machine, combinations of the same, or the like. A processor caninclude electrical circuitry configured to process computer-executableinstructions. In another embodiment, a processor includes an FPGA orother programmable device that performs logic operations withoutprocessing computer-executable instructions. A processor can also beimplemented as a combination of computing devices, for example, acombination of a DSP and a microprocessor, a plurality ofmicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration. Although described hereinprimarily with respect to digital technology, a processor may alsoinclude primarily analog components. For example, some or all of thesignal processing algorithms described herein may be implemented inanalog circuitry or mixed analog and digital circuitry. A computingenvironment can include any type of computer system, including, but notlimited to, a computer system based on a microprocessor, a mainframecomputer, a digital signal processor, a portable computing device, adevice controller, or a computational engine within an appliance, toname a few.

Conditional language such as, among others, “can,” “could,” “might” or“may,” unless specifically stated otherwise, are otherwise understoodwithin the context as used in general to convey that certain embodimentsinclude, while other embodiments do not include, certain features,elements and/or steps. Thus, such conditional language is not generallyintended to imply that features, elements and/or steps are in any wayrequired for one or more embodiments or that one or more embodimentsnecessarily include logic for deciding, with or without user input orprompting, whether these features, elements and/or steps are included orare to be performed in any particular embodiment.

Disjunctive language such as the phrase “at least one of X, Y, or Z,”unless specifically stated otherwise, is otherwise understood with thecontext as used in general to present that an item, term, etc., may beeither X, Y, or Z, or any combination thereof (for example, X, Y, and/orZ). Thus, such disjunctive language is not generally intended to, andshould not, imply that certain embodiments require at least one of X, atleast one of Y, or at least one of Z to each be present.

Any process descriptions, elements or blocks in the flow diagramsdescribed herein and/or depicted in the attached figures should beunderstood as potentially representing modules, segments, or portions ofcode which include one or more executable instructions for implementingspecific logical functions or elements in the process. Alternateimplementations are included within the scope of the embodimentsdescribed herein in which elements or functions may be deleted, executedout of order from that shown, or discussed, including substantiallyconcurrently or in reverse order, depending on the functionalityinvolved as would be understood by those skilled in the art.

Unless otherwise explicitly stated, articles such as “a” or “an” shouldgenerally be interpreted to include one or more described items.Accordingly, phrases such as “a device configured to” are intended toinclude one or more recited devices. Such one or more recited devicescan also be collectively configured to carry out the stated recitations.For example, “a processor configured to carry out recitations A, B andC” can include a first processor configured to carry out recitation Aworking in conjunction with a second processor configured to carry outrecitations B and C.

It should be emphasized that many variations and modifications may bemade to the above-described embodiments, the elements of which are to beunderstood as being among other acceptable examples. All suchmodifications and variations are intended to be included herein withinthe scope of this disclosure.

What is claimed is:
 1. A computer-implemented method for executing agame application on a user computing system: by one or more hardwareprocessor configured with computer executable instructions, executing agame application; executing a plurality of simulation engines within thegame application, wherein each simulation engine is configured toexecute game logic that is configured to control simulation of a virtualenvironment within the game application, wherein each simulation engineis configured to control simulation of a different virtual environment,wherein each virtual environment comprises a plurality of virtualobjects registered to the corresponding simulation engine; for eachsimulation engine, generating simulation state data for each virtualobject registered to the simulation engine during a simulation cycle;generating graphical state data based at least in part on the simulationstate data generated for the simulation cycle; writing the graphicalstate data for a least a subset of the virtual objects to a state datapackage during the simulation cycle; after the graphical state data foreach virtual object has been written to the state data package, writingthe state data package to a state stream during the simulation cycle,wherein the state stream is a portion of volatile memory allocated toreceive the state data package; executing a presentation engine withinthe game application, wherein the presentation engine is configured togenerate and render frames for output on a display; selecting, by thepresentation engine, at least a first state data package of a pluralityof state data packages during a rendering cycle; reading, by thepresentation engine, at least the first state data package from thestate stream during the rendering cycle; updating, by the presentationengine, a graphical state of first virtual environment corresponding tothe virtual environment associated with the first state data package,generating, by the presentation engine, a frame based at least in parton the updated graphical state of the first virtual environment and asecond state data package, wherein the second state data package wasgenerated by the same simulation engine that generated the first statedata package; and rendering, by the presentation engine, the frame basedat least in part on the graphical state data included in the first statedata package and the second state data package during the renderingcycle, wherein the presentation engine state data package generates,wherein the presentation engine executes the rendering cycles withoutfurther input from the simulation engines after receiving the state datapackages.
 2. The computer-implemented method of claim 1, wherein thesimulation cycle and the rendering cycle are the different lengths oftime.
 3. The computer-implemented method of claim 2 further comprisinginterpolating the graphical state data included in the first state datapackage and the second state data package; generating a plurality offrames based on the interpolation; and rendering the plurality offrames.
 4. The computer-implemented method of claim 1, wherein thesimulation cycles for each simulation engine are different lengths oftime relative to each other.
 5. The computer-implemented method of claim1, wherein the each of the plurality of simulation engines executeindependent of each other and the presentation engine, wherein thepresentation engine generates and renders frames independent of theexecution of simulation engine that generated the state data package. 6.The computer-implemented method of claim 1 further comprising executingone or more simulation engines on different user computing systems andwriting state data packages to the state stream on the user computingsystem over a network.
 7. The computer-implemented method of claim 1further comprising, by each simulation engine, writing state datapackage to a location in non-volatile storage simultaneously withwriting the state data package to the state stream.
 8. Thecomputer-implemented method of claim 1, wherein each simulation enginewrites to a different state stream, and each state stream is allocated adifferent portion of volatile memory to receive the state data package.9. The computer-implemented method of claim 1 further comprising:determining, by the presentation engine, an state data package is readyfor disposal; and deleting the state data packages from the state streamthat are ready for disposal.
 10. The computer-implemented method ofclaim 1, wherein the graphical state data of a state data packagecomprises state data necessary to recreate a graphical scene within therespective virtual environment of the corresponding simulation engine ata point in time.
 11. The computer-implemented method of claim 1, whereinthe state data package is generated in less time that the length of thesimulation cycle, wherein there is a period of time between writing thestate data package to the state stream and the initiation of thesubsequent simulation cycle.
 12. A computing system comprising: one ormore hardware processors configured with computer-executableinstructions that configure the computing system to: execute a gameapplication; execute a plurality of simulation engines within the gameapplication, wherein each simulation engine is configured to executegame logic that is configured to control simulation of a virtualenvironment within the game application, wherein each simulation engineis configured to control simulation of a different virtual environment,wherein each virtual environment comprises a plurality of virtualobjects registered to the corresponding simulation engine; for eachsimulation engine, generate simulation state data for each virtualobject registered to the simulation engine during a simulation cycle;generate graphical state data based at least in part on the simulationstate data generated for the simulation cycle; write the graphical statedata for a least a subset of the virtual objects to a state data packageduring the simulation cycle; after the graphical state data for eachvirtual object has been written to the state data package, write thestate data package to a state stream during the simulation cycle,wherein the state stream is a portion of volatile memory allocated toreceive the state data package; execute a presentation engine within thegame application, wherein the presentation engine is configured togenerate and render frames for output on a display; select, by thepresentation engine, at least a first state data package of a pluralityof state data packages during a rendering cycle; read, by thepresentation engine, at least the first state data package from thestate stream during the rendering cycle; update, by the presentationengine, a graphical state of first virtual environment corresponding tothe virtual environment associated with the first state data package,generate, by the presentation engine, a frame based at least in part onthe updated graphical state of the first virtual environment and asecond state data package, wherein the second state data package wasgenerated by the same simulation engine that generated the first statedata package; and render, by the presentation engine, the frame based atleast in part on the graphical state data included in the first statedata package and the second state data package during the renderingcycle, wherein the presentation engine state data package generates,wherein the presentation engine executes the rendering cycles withoutfurther input from the simulation engines after receiving the state datapackages.
 13. The system of claim 12, wherein the simulation cycle andthe rendering cycle are the different lengths of time.
 14. The system ofclaim 13 wherein the one or more processors are configured withcomputer-executable instructions that further configure the presentationengine to interpolate the graphical state data included in the firststate data package and the second state data package, generate aplurality of frames based on the interpolation, and render the pluralityof frames.
 15. The system of claim 12, wherein the simulation cycles foreach simulation engine are different lengths of time relative to eachother.
 16. The system of claim 12, wherein the one or more processorsare configured with computer-executable instructions that furtherconfigure each of the plurality of simulation engines to executeindependent of each other and the presentation engine, the presentationengine to generate and render frames independent of the execution ofsimulation engine that generated the state data package.
 17. The systemof claim 12, wherein the one or more processors are configured withcomputer-executable instructions that further configure each simulationengine to write the state data package to a location in non-volatilestorage simultaneously with writing the state data package to the statestream.
 18. The system of claim 12, wherein the one or more processorsare configured with computer-executable instructions that furtherconfigure each simulation engine writes to a different state stream, andeach state stream is allocated a different portion of volatile memory toreceive the state data package.
 19. The system of claim 12, wherein thegraphical state data of a state data package comprises state datanecessary to recreate a graphical scene within the respective virtualenvironment of the corresponding simulation engine at a point in time.20. The system of claim 12, wherein the state data package is generatedin less time that the length of the simulation cycle, wherein there is aperiod of time between writing the state data package to the statestream and the initiation of the subsequent simulation cycle.